Typically, as exemplified in Nikolich U.S. Pat. Re. 32,452, Nikolich U.S. Pat. No. 4,522,162, Nikolich U.S. Pat. No. 4,483,474, Nikolich U.S. Pat. No. 4,403,722, and Wagdy U.S. Pat. No. 4,483,473, a combustion-powered, fastener-driving tool comprises a combustion chamber, which is defined by a cylinder body and by a valve sleeve arranged for opening and closing the combustion chamber. Generally similar, combustion-powered, nail- and staple-driving tools are available commercially from ITW-Paslode (a unit of Illinois Tool Works Inc.) of Lincolnshire, Ill., under its IMPULSE trademark.
Typically, in such a tool, a housing structure encloses a cylinder body, which defines a tool axis, and within which a piston is mounted operatively. A valve sleeve is mounted in movable relation to the cylinder body so as to open and close a combustion chamber defined by the cylinder body and the valve sleeve. A nosepiece is mounted to the housing structure, in axially spaced relation to the cylinder body, via a separate piece defining a lower chamber between the cylinder body and the nosepiece.
A linkage is used to close the combustion chamber when an element of the linkage contacts a workpiece. Plural arms of the linkage are connected to the valve sleeve by fasteners and are connected to the workpiece-contacting element by an intermediate element disposed within the lower chamber and across the tool axis. The linkage arms extend outwardly from the lower chamber, through outer apertures, and upwardly along the cylinder body. The lower chamber provides axial clearance, e.g. about one inch of axial clearance, to permit axial movement of the arms and intermediate element of the linkage relative to the cylinder body, the nosepiece, and the housing structure.
This invention has resulted from efforts to redesign such a tool so as to reduce its axial length and its overall weight. Even small reductions in the length and weight of such a tool can meaningfully increase its versatility.